1. Field
The present disclosure relates to a refrigerator.
2. Background
Refrigerators are home appliances for storing foods at a low temperature. Such a refrigerator has one or both of a refrigerating compartment storing foods in a refrigerated state and a freezing compartment storing foods in a frozen state. In recent years, a dispenser is mounted on a front surface of a refrigerator door to dispense drinking water without opening the refrigerator door. In addition, an ice maker for making and storing ice cubes may be provided in a door or a storage space of refrigerator. Thus, the ice cubes may be dispensed through the dispenser.
In the related art, there is a hot water supply system for a cold and hot water dispenser. For example, Korean Patent Publication No. 10-2012-0112060 discloses a device and method for supplying hot water. The related art discloses a method of controlling an instantaneous heating device applied to the hot water supply system of the cold and hot water dispenser. For example, a technology is disclosed for regulating an amount of inflow water according to a target water temperature, an inflow water temperature, and heating capacity of a heater.
According to the related art, a water flow sensor measures a flow rate of water passing through an inflow valve, and an opening degree or opening/closing of the inflow valve is controlled again by using the measured flow rate as feedback information. There is a high variation in flow rate measured by the water flow sensor, and an error in the water flow sensor itself is non-negligible. As a result, it is difficult to a water temperature desired by consumer in spite of precise control. In such a control method, there is a considerable variation in temperature of the first cup for hot water.
Due to this limitation, a heater is additionally feedback-controlled in the related art to attain a desired water temperature, and yet the desired water temperature is not attainable. In addition, a heating time of an instantaneous heating device has a constant value or depends upon an external input, and thus, it is difficult to control a water temperature as desired. Further, since the timing of water discharge is not determined, consumers may not obtain water with an accurate temperature. In the related art, hot water with an accurate temperature may not be supplied due to this limitation. In addition, it is not possible to secure safety in a heater.